1. Field of the Invention
The present invention relates to wireless communication apparatuses that communicate between a master unit and a slave unit.
2. Discussion of the Background
Cycle computers are used to display riding information such as bicycle speed and riding distance. For example, such a cycle computer can include a rotation sensor and a parameter display device, wherein the rotation sensor outputs rotation signals in accordance with the rotation of a wheel, and the riding parameter display device displays bicycle speed and riding distance in response to the output rotation signals.
It is also known to transmit the rotation signals wirelessly from the rotation sensor to the display device, as is evident from a review of Japanese unexamined patent application publication 3-12798. The device described therein includes a display unit and a signal generating unit for generating the rotation signals. The display unit and the signal generating unit each operate using a battery as the power source. Since a battery is used as the power source for the various components, once the battery is expended, the device does not operate until the battery is replaced. Thus, due to the limited amount of power supply available for the device, improvements are needed to conserve the power supply.